Fatal SARS-CoV-2 Infection among Children, Japan, January-September 20221.

To determine the characteristics of pediatric patients 0-19 years of age who died after onset of SARS-CoV-2 infection in Japan during January 1-September 30, 2022, we reviewed multiple sources. We identified 62 cases, collected detailed information from medical records and death certificates, and conducted interviews, resulting in 53 patients with detailed information for our study. Among 46 patients with internal causes of death (i.e., not external causes such as trauma), 15% were <1 year of age, 59% had no underlying disease, and 88% eligible for vaccination were unvaccinated. Nonrespiratory symptoms were more common than respiratory symptoms. Out-of-hospital cardiac arrest affected 46% of patients, and time from symptom onset to death was <7 days for 77%. Main suspected causes of death were central nervous system abnormalities (35%) and cardiac abnormalities (20%). We recommend careful follow-up of pediatric patients after SARS-CoV-2 infection during the first week after symptom onset, regardless of underlying diseases.

Curcumin activates G protein-coupled receptor 97 (GPR97) in a manner different from glucocorticoid.

Curcumin is a yellow pigment in turmeric (Curcuma longa) with various physiological effects in the body. To elucidate the molecular mechanisms by which bioactive compounds exert their function, identification of their molecular targets is crucial. In this study, we show that curcumin activates G protein-coupled receptor 97 (GPR97). Curcumin dose-dependently activated serum-response element-, but not serum-response factor-response element-, nuclear factor of activated T-cell-response element-, or cAMP-response element-, mediated transcription in cells overexpressed with GPR97. The structure-activity relationship indicated that (i) the double-bonds of the central 7-carbon chain were essential for activation; (ii) a methoxy group on the aromatic ring was required for maximal activity; (iii) the addition of glucuronic acid moiety or a methoxy group to the aromatic ring, but not the methylation of the aromatic p-hydroxy group, eliminated the activity; (iv) the stability of curcumin would be related to receptor activation. Both mutant GPR97(T250A) lacking the cleavage at GPCR proteolysis site and mutant GPR97(ΔN) lacking the N-terminal extracellular region were activated by curcumin and its related compounds similar to wild-type GPR97. In contrast, the synthetic glucocorticoid beclomethasone dipropionate and l-Phe activated wild-type GPR97 and GPR97(T250A), but not GPR97(ΔN). Moreover, curcumin exerted an additive effect on the activation of wild-type GPR97 with beclomethasone dipropionate, but not with l-Phe. Taken together, these results indicate that curcumin activates GPR97 coupled to Gi/Go subunit, and suggest that curcumin and glucocorticoid activate GPR97 in a different manner.

Adverse Event Following Immunization Monitoring System in Japan.

Although immunization is essential for maintaining public health, adverse events following immunization (AEFI) occur at a certain rate. Therefore, it is extremely important to conduct postimmunization safety monitoring and relief systems to ensure the safe implementation of immunizations for the public. This article summarizes the monitoring system of AEFI and the unique compensation system (so-called relief system) in Japan. In addition, current problems and issues on the AEFI monitoring and relief system will be specified, and immunization-related systems planned to be built in the future in Japan will be introduced.

National seroepidemiological study of COVID-19 after the initial rollout of vaccines: Before and at the peak of the Omicron-dominant period in Japan.

Background: Based on routine surveillance data, Japan has been affected much less by COVID-19 compared with other countries. To validate this, we aimed to estimate SARS-CoV-2 seroprevalence and examine sociodemographic factors associated with cumulative infection in Japan. Methods: A population-based serial cross-sectional seroepidemiological investigation was conducted in five prefectures in December 2021 (pre-Omicron) and February-March 2022 (Omicron [BA.1/BA.2]-peak). Anti-nucleocapsid and anti-spike antibodies were measured to detect infection-induced and vaccine/infection-induced antibodies, respectively. Logistic regression was used to identify associations between various factors and past infection. Results: Among 16 296 participants (median age: 53 [43-64] years), overall prevalence of infection-induced antibodies was 2.2% (95% CI: 1.9-2.5%) in December 2021 and 3.5% (95% CI: 3.1-3.9%) in February-March 2022. Factors associated with past infection included those residing in urban prefectures (Tokyo: aOR 3.37 [95% CI: 2.31-4.91], Osaka: aOR 3.23 [95% CI: 2.17-4.80]), older age groups (60s: aOR 0.47 [95% CI 0.29-0.74], 70s: aOR 0.41 [95% CI 0.24-0.70]), being vaccinated (twice: aOR 0.41 [95% CI: 0.28-0.61], three times: aOR 0.21 [95% CI: 0.12-0.36]), individuals engaged in occupations such as long-term care workers (aOR: 3.13 [95% CI: 1.47-6.66]), childcare workers (aOR: 3.63 [95% CI: 1.60-8.24]), food service workers (aOR: 3.09 [95% CI: 1.50-6.35]), and history of household contact (aOR: 26.4 [95% CI: 20.0-34.8]) or non-household contact (aOR: 5.21 [95% CI:3.80-7.14]) in February-March 2022. Almost all vaccinated individuals (15 670/15 681) acquired binding antibodies with higher titers among booster dose recipients. Conclusions: Before Omicron, the cumulative burden was >10 times lower in Japan (2.2%) compared with the US (33%), the UK (25%), or global estimates (45%), but most developed antibodies owing to vaccination.

Identification of G protein-coupled receptor 55 (GPR55) as a target of curcumin.

The identification of molecular targets of bioactive food components is important to understand the mechanistic aspect of their physiological functions. Here, we have developed a screening system that enables us to determine the activation of G protein-coupled receptors (GPCRs) by food components and have identified GPR55 as a target for curcumin. Curcumin activated GPR55 and induced serum-response element- and serum-response factor-mediated transcription, which were inhibited by Rho kinase and GPR55 antagonists. Both the methoxy group and the heptadienone moiety of curcumin were required for GPR55 activation. The F1905.47 residue of GPR55 was important for the interaction with curcumin. The curcumin-induced secretion of glucagon-like peptide-1 in GLUTag cells was inhibited by a GPR55 antagonist. These results indicate that expression screening is a useful system to identify GPCRs as targets of food components and strongly suggest that curcumin activates GPR55 as an agonist, which is involved in the physiological function of curcumin.

Vasovagal reactions after COVID-19 vaccination in Japan.

Coronavirus disease 2019 (COVID-19) vaccine administration started in February 2021 in Japan. As of December 2021, approximately 75% of the population aged ≥12 years had received two doses of vaccine. We conducted a study to investigate vasovagal reactions (VVR) after COVID-19 vaccination using data on adverse events following immunization. The crude reporting rate of VVR (cases/1,000,000 doses) after vaccination was 9.6 in all age groups combined, and was more frequent in the younger age groups: 28.6 and 37.2 in individuals aged 10-19 years and 20-29 years, respectively. In individuals aged 10-29 years, the rate was similar in males and females (33.0 and 34.2, respectively, p = 0.53); but was higher after dose 1 than after dose 2 (57.4 and 8.8, respectively, p < 0.001). Based on these results, caution needs to be exercised when vaccinating adolescents and young adults, especially with dose 1 of COVID-19 vaccines.

Vitamin D Supplementation Regulates Postoperative Serum Levels of PD-L1 in Patients with Digestive Tract Cancer and Improves Survivals in the Highest Quintile of PD-L1: A Post Hoc Analysis of the AMATERASU Randomized Controlled Trial.

Because vitamin D responsive elements have been found to be located in the PD-L1 gene, vitamin D supplementation was hypothesized to regulate serum PD-L1 levels and thus alter survival time of cancer patients. A post hoc analysis of the AMATERASU randomized, double-blind, placebo-controlled trial of postoperative vitamin D3 supplementation (2000 IU/day) in 417 patients with stage I to stage III digestive tract cancer from the esophagus to the rectum was conducted. Postoperative serum PD-L1 levels were measured by ELISA and divided into quintiles (Q1-Q5). Serum samples were available for 396 (95.0%) of the original trial. Vitamin D supplementation significantly (p = 0.0008) up-regulated serum PD-L1 levels in the lowest quintile (Q1), whereas it significantly (p = 0.0001) down-regulated them in the highest quintile (Q5), and it did not either up- or down-regulate them in the middle quintiles (Q2-Q4). Significant effects of vitamin D supplementation, compared with placebo on death (HR, 0.34; 95% CI, 0.12-0.92) and relapse/death (HR, 0.37; 95% CI, 0.15-0.89) were observed in the highest quintile (Q5) of serum PD-L1, whereas significant effects were not observed in other quintiles (Pinteraction = 0.02 for death, Pinteraction = 0.04 for relapse/death). Vitamin D supplementation significantly reduced the risk of relapse/death to approximately one-third in the highest quintile of serum PD-L1.

Effect of Vitamin D Supplementation on Survival of Digestive Tract Cancer Patients with Low Bioavailable 25-Hydroxyvitamin D levels: A Post Hoc Analysis of the AMATERASU Randomized Clinical Trial.

Vitamin D has been shown to suppress the growth of cancer cells. Cancer cells are believed to take up bioavailable 25-hydroxyvitamin D (25[OH]D) (i.e., not bound to vitamin-D-binding protein (DBP)) more efficiently than DBP-bound 25(OH)D. Our aim was to use this bioavailable 25(OH)D, rather than total 25(OH)D, as a biomarker of vitamin D deficiency to investigate whether vitamin D supplementation improves the relapse-free survival (RFS) of patients with digestive tract cancer from the esophagus to the rectum by conducting a post hoc analysis of the AMATERASU trial (UMIN000001977). The bioavailable 25(OH)D levels were calculated via an equation using data of serum total 25(OH)D, albumin, and DBP levels, and DBP genotypes (rs7041 and rs4588). We estimated bioavailable 25(OH) levels in 355 patients. In a subgroup of patients with low bioavailable 25(OH)D levels (

Effect of Avoiding Cow's Milk Formula at Birth on Prevention of Asthma or Recurrent Wheeze Among Young Children: Extended Follow-up From the ABC Randomized Clinical Trial.

Importance: Children with food allergies may develop asthma or recurrent wheeze. Objective: To evaluate whether asthma or recurrent wheeze among children were changed by avoiding supplementing breastfeeding (BF) with cow's milk formula (CMF) in the first 3 days of life. Design, Setting, and Participants: This randomized, unmasked, clinical trial was conducted at 1 university hospital in Japan beginning October 2013 with follow-up examinations occurring until January 2020. A total of 312 newborns at risk for atopy were randomized and assigned to either BF with or without amino acid-based elemental formula (EF) or BF with CMF, with follow-up examinations for participants showing signs of atopy conducted at 24 months. Follow-up examinations ran through January 2020. Interventions: Immediately after birth, newborns were randomly assigned (1:1 ratio) to either breastfeeding with or without amino acid-based elemental formula for at least the first 3 days of life (no CMF group) or breastfeeding supplemented with CMF (≥5 mL/d) from the first day of life to 5 months of age (CMF group). Main Outcomes and Measures: Asthma or recurrent wheeze diagnosed by the pediatric allergy specialists of this trial; subgroups were stratified by serum levels of 25-hydroxyvitamin D and IgE. Results: Of 312 infants (156 [50.0%] randomized to the no CMF group), 302 (96.8%) were followed up at their second birthday: 77 of 151 (51.0%) in the no CMF group and 81 of 151 (53.6%) in the CMF group underwent extended follow-up because of having atopic conditions. Asthma or recurrent wheeze developed in 15 (9.9%) of the children in the no CMF group, significantly less than the children in the CMF group (27 [17.9%]; risk difference, -0.079; 95% CI, -0.157 to -0.002). In participants with vitamin D levels above the median at 5 months of age, asthma or recurrent wheeze developled in 5 (6.4%) children in the no CMF group, significantly less than in the children in the CMF group (17 [24.6%]; risk difference, -0.182; 95% CI, -0.298 to -0.067; P for interaction = .04). In the highest quartile group of total IgE at age 24 months, asthma or recurrent wheeze developed in 2 children (5.3%) in the no CMF group, significantly less than the children in the CMF group (14 [43.8%]; risk difference, -0.385; 95% CI, -0.571 to -0.199; P for interaction = .004). Conclusions and Relevance: The findings of this study suggest that avoiding CMF supplementation in the first 3 days of life has the potential to reduce the risk of asthma or recurrent wheeze in young children, especially among those with high vitamin D or high IgE levels. Trial Registration: umin.ac.jp/ctr Identifier: UMIN000011577.

Elevated Soluble PD-L1 in Pregnant Women's Serum Suppresses the Immune Reaction.

Background: Programmed death-ligand 1 (PD-L1) is expressed not only on some cancer cells, but also on the outer surface of placental syncytiotrophoblasts, which is assumed to induce maternal immune tolerance to fetal tissue via programmed death-1 (PD-1) receptors on T cells. Recently, levels of soluble forms of PD-L1 (sPD-L1) were reported to be higher in the serum of pregnant women (PW) than in non-pregnant women (non-PW). However, there have been no reports of the functional significance of PW's serum containing high sPD-L1 levels. Therefore, the aim of the present study was to clarify the role of sPD-L1 in the sera of PW as an immunosuppressive molecule by in vitro assays. Methods: As a post-hoc analysis of our previous cohort study, 330 pairs of serum from PW during the third trimester and cord blood (CB) from paired offspring without major complications were examined. Serum levels of sPD-L1 and sPD-1 were measured by ELISA. On mixed lymphocyte culture (MLC), 3H-thymidine uptakes in the presence of PW's, offspring's, or non-PW's serum were compared. Peripheral blood mononuclear cells (PBMCs) were cultured in the presence of PW's serum stimulated with PHA, and then cytokine levels were measured in supernatants by multiple cytokine analysis with or without anti-PD-L1blocking antibody. Results: The median sPD-L1 level was 8.3- and 6.9-fold higher in PW than in offspring and non-PW, respectively, whereas sPD-1 levels were lower in PW and offspring than in non-PW. On MLC, 3H-thymidine uptake in the presence of autoantigen was strongly reduced by co-culture with serum of both PW and offspring, compared with serum of non-PW. In contrast, uptake in the presence of alloantigen was moderately inhibited by PW's serum, whereas it was less suppressed by offspring's serum, compared with non-PW's serum. In the culture of PBMCs, tumor necrosis factor-α, interferon gamma, interleukin (IL)-2, and IL-4 levels were significantly higher in the presence of anti-PD-L1 blocking antibody than in culture not treated with antibody (all P < 0.05) or culture treated with isotype control antibody (all P < 0.05). Conclusion: The levels of sPD-L1 are elevated in PW's serum, which may, at least in part, suppress maternal immunity.

2-Phenylquinoline-Sugar Hybrids as Photoswitchable α-Glucosidase Inhibitors.

Purpose-designed 2-phenylquinoline (PQ)-sugar hybrids 1 and 2 were synthesized and evaluated for their photodegradation activities against an α-glucosidase target. The results indicated that PQ-mannose hybrid 2 selectively and effectively photodegraded α-glucosidase and significantly inhibited its enzymatic activity upon irradiation with long-wavelength UV light in the absence of any additives under neutral and aqueous conditions. Furthermore, 2 selectively and effectively inhibited α-glucosidase activity only with photo-irradiation even in complex cell lysate.

Primary Prevention of Cow's Milk Sensitization and Food Allergy by Avoiding Supplementation With Cow's Milk Formula at Birth: A Randomized Clinical Trial.

Importance: Cow's milk formula (CMF) is used to supplement breastfeeding (BF) at birth without clear clinical evidence to support the practice. Objective: To determine whether avoiding supplementation with CMF at birth can decrease risks of sensitization to cow's milk protein and/or clinical food allergy, including cow's milk allergy (CMA), overall and in subgroups stratified by 25-hydroxyvitamin D (25[OH]D) levels. Design, Setting, and Participants: The Atopy Induced by Breastfeeding or Cow's Milk Formula (ABC) trial, a randomized, nonblinded clinical trial, began enrollment October 1, 2013, and completed follow-up May 31, 2018, at a single university hospital in Japan. Participants included 330 newborns at risk for atopy; of these, 312 were included in the analysis. Data were analyzed from September 1 through October 31, 2018. Interventions: Immediately after birth, newborns were randomized (1:1 ratio) to BF with or without amino acid-based elemental formula (EF) for at least the first 3 days of life (BF/EF group) or BF supplemented with CMF (≥5 mL/d) from the first day of life to 5 months of age (BF plus CMF group). Main Outcomes and Measures: The primary outcome was sensitization to cow's milk (IgE level, ≥0.35 allergen units [UA]/mL) at the infant's second birthday. Secondary outcomes were immediate and anaphylactic types of food allergy, including CMA, diagnosed by oral food challenge test or triggered by food ingestion, with food-specific IgE levels of at least 0.35 UA/mL. Subgroup analysis was prespecified by tertiles of serum 25(OH)D levels at 5 months of age. Results: Of the 312 infants included in the analysis (160 female [51.3%] and 152 male [48.7%]), 151 of 156 (96.8%) in the BF/EF and BF plus CMF groups were followed up until their second birthday. The primary outcome occurred in 24 infants (16.8%) in the BF/EF group, which was significantly fewer than the 46 infants (32.2%) in the BF plus CMF group (relative risk [RR], 0.52; 95% CI, 0.34-0.81). The middle tertile of the 25(OH)D subgroup, but not the low and high tertiles, had a significant interaction with the intervention (RR, 0.19; 95% CI, 0.07-0.50; P = .02). The prevalence of food allergy at the second birthday was significantly lower in the BF/EF than in the BF plus CMF groups for immediate (4 [2.6%] vs 20 [13.2%]; RR, 0.20; 95% CI, 0.07-0.57) and anaphylactic (1 [0.7%] vs 13 [8.6%]; RR, 0.08; 95% CI, 0.01-0.58) types. Conclusions and Relevance: The evidence suggests that sensitization to cow's milk and food allergy, including CMA and anaphylaxis, are primarily preventable by avoiding CMF supplementation for at least the first 3 days of life. Trial Registration: http://umin.ac.jp Identifier: UMIN000011577.

Tomatidine Reduces Palmitate-Induced Lipid Accumulation by Activating AMPK via Vitamin D Receptor-Mediated Signaling in Human HepG2 Hepatocytes.

SCOPE: Nonalcoholic fatty liver disease (NAFLD) has emerged as the most common chronic liver disease worldwide, defined by hepatic over-accumulation of lipids without significant ethanol consumption. Pharmacological or bioactive food ingredients that suppress hepatic lipid accumulation through AMP-activated protein kinase (AMPK) signaling, which plays a critical role in the regulation of lipid metabolism, are searched. METHODS AND RESULTS: It is found that tomatidine, the aglycone of α-tomatine abundant in green tomatoes, significantly inhibits palmitate-provoked lipid accumulation and stimulates phosphorylation of AMPK and acetyl-CoA carboxylase 1 (ACC1) in human HepG2 hepatocytes. The results also indicate that tomatidine can enhance triglyceride turnover and decline in lipogenesis by upregulating adipose triglyceride lipase (ATGL) and downregulating fatty acid synthase (FAS) via the AMPK signaling-dependent regulation of transcription factors, element-binding protein-1c (SREBP-1c) and forkhead box protein O1 (FoxO1). Furthermore, mechanistic studies demonstrate that tomatidine-stimulated AMPK phosphorylation is due to CaMKKß activation in response to an increase in intracellular Ca2+ concentration. Finally, it is discovered that tomatidine functions as an agonist for vitamin D receptor to elicit AMPK-dependent suppression of lipid accumulation. CONCLUSION: The in vitro study suggests the potential efficacy of tomatidine as a preventive and therapeutic treatment in obesity-related fatty liver diseases.

Target-selective photo-degradation of AFP-L3 and selective photo-cytotoxicity against HuH-7 hepatocarcinoma cells using an anthraquinone-PhoSL hybrid.

A purposefully-designed anthraquinone-Pholiota squarrosa lectin (PhoSL) hybrid effectively degraded α-fetoprotein-L3 (AFP-L3) associated with liver cancer. Degradation was achieved under light irradiation in the absence of any additives and under neutral pH conditions. Moreover, the hybrid effectively exhibited selective photo-cytotoxicity against HuH-7 hepatocarcinoma cells upon photo-irradiation.